CT (Computed Tomography) model expansion modeling and application method and system for representing equipment association relationship

Abstract

The invention discloses a CT (Computed Tomography) model expansion modeling and application method and system for representing equipment incidence relation. The method comprises the following steps: expanding a Private object for a CT model to perfect a coil model of the CT model; establishing an association relationship between the LN of the protection device and the coil model according to different sampling modes of the protection device; and carrying out fault positioning according to a CT model comprising the coil model and the association relationship between the coil model and the logic node LN of the protection device. According to the method, the primary model of the transformer substation is perfected and improved, digitization of the structure of the transformer substation is facilitated, the sampling range of protection can be determined more accurately, then accurate positioning of faults between coils can be achieved, coil configuration rules can be formulated, and the correctness of protection sampling configuration can be checked.

Description

Technical Field

[0001] The invention belongs to the technical field of relay protection, and relates to a CT model extension modeling and application method and system for characterizing equipment association relationship. Background Art

[0002] In recent years, my country's smart substations have developed rapidly, and the emergence of high-reliability smart substations marks a new stage in the construction of smart substations. The IEC 61850 standard compiled by IEC TC57 is the basis for the construction of smart substations. The IEC 61850 standard defines the system specification description SSD file, which can carry the primary system structure of the substation and the relationship between the primary and secondary equipment models. Through the relationship between the primary and secondary equipment, it is possible to obtain information such as which secondary equipment (such as protection device) LN is associated with a certain primary equipment (such as voltage transformer CT), and which secondary equipment LN is associated with the same bay. Its importance is becoming increasingly noticeable.

[0003] In the existing smart substation design and integration process, the secondary equipment LN is usually not associated in the SSD file, or the existing primary and secondary association method cannot fully describe the characteristics of the CT, and the coil model is missing. The lack of this association relationship leads to unclear associations between the primary and secondary equipment in the substation, which in turn results in a poor data foundation for advanced applications based on the status of primary and secondary equipment and the status information between secondary equipment in the interval, which is not conducive to the precise positioning of faults in the later stage. Although the configuration process can be realized directly facing the instantiated specific device model, it is not convenient for the reuse of interval configuration results, and the impact on configuration efficiency and quality is undoubtedly negative. In addition, the unclear association between the primary and secondary equipment in the substation also brings great obstacles to the application of SSD files.

[0004] The current existing technologies usually only focus on how to use the correlation between the SSD model and the primary and secondary models to achieve fast and automatic connection of the virtual terminals of the smart substation, which solves the problem of efficiency and does not involve the completion of the missing CT model of the existing smart substation. Summary of the invention

[0005] In order to solve the deficiencies in the prior art, the present invention provides a CT model extension modeling and application method and system for characterizing the equipment association relationship, so as to complete the missing CT model of the existing smart substation. Through the CT model extension modeling of the SSD file, the definition of the CT coil and polarity is expanded, the association relationship between the related primary and secondary equipment is clarified, the problem of incomplete CT model of the current smart substation is solved, the configuration efficiency is improved, and the accurate analysis and positioning of faults are realized.

[0006] The present invention adopts the following technical solution.

[0007] A first aspect of the present invention provides a CT model extension modeling and application method for characterizing device association relationships, comprising:

[0008] The private object Private is extended for the current transformer CT model to improve the coil model of the CT model;

[0009] According to different sampling modes of the protection device, an association relationship between the logical node LN of the protection device and the coil model is established;

[0010] Fault location is performed based on the CT model including the coil model and its association with the logical node LN of the protection device.

[0011] Preferably, the step of extending the private object Private of the current transformer CT model to improve the coil model of the CT model includes:

[0012] Under the CT model element of ConductingEquipment of type type="CTR", a Private is extended, whose type attribute is "Homonymous Terminal", representing the homonymous terminal, and whose value is the name of the CT terminal Terminal close to the homonymous terminal;

[0013] A Private is extended for each coil of the CT model, the type attribute value of which is winding Winding, and the extended name xmlns is coil = "coil.paras.com";

[0014] Define coil:no sub-element, coil:parameter sub-element and coil:LNode sub-element under Private extended by the coil.

[0015] Preferably, the coil:no sub-element indicates the corresponding coil number and includes the attribute name;

[0016] The coil:parameter sub-element represents the parameters of the coil, and includes the attributes name, desc, dimension and value, which represent the name, description, dimension and value respectively;

[0017] The coil:LNode sub-element represents the logical node of the secondary device associated with the coil, and contains the attributes lnInst, lnClass, prefix, ldInst, and iedName, which respectively represent the LN instance, logical node type, prefix, LD instance, and IED name, which are used to reference the logical node associated with the merging unit, so that the protection device can indirectly obtain the corresponding CT model coil through the virtual circuit relationship with the merging unit.

[0018] Preferably, under the coil Private object extended by a coil, there is one and only one coil:no sub-element, and multiple coil:parameter sub-elements and coil:LNode sub-elements are allowed to be defined.

[0019] Preferably, the sampling method includes a digital sampling method and an analog sampling method.

[0020] Preferably, if the protection device adopts a digital sampling method, the logical node "TCTR" under the process layer access point of the merging unit or the acquisition execution unit is associated with the coil model; the protection device obtains the corresponding sampling virtual signal through the relationship of the process layer virtual loop, and then indirectly obtains the coil involved in the protection sampling.

[0021] Preferably, if the protection device adopts an analog sampling method, the logical node "MMXU" under the station control layer access point of the protection device is associated with the corresponding coil model.

[0022] Preferably, the fault location is performed according to the CT model including the coil model and the association relationship between the coil model and the logical node LN of the protection device, including:

[0023] According to the CT model including the coil model and its association relationship with the logical node LN of the protection device, the required secondary device information is obtained through its associated logical node LN, and the association relationship between the enumeration signal of the secondary device and the actual signal description is established according to the secondary device information;

[0024] Based on the correspondence between the name of the secondary equipment information and the name of the recording channel, the relevant recording channels are automatically matched according to the same name, and homologous comparison and differential current analysis are carried out based on the recording channels. The fault position is located according to the results of homologous comparison and differential current analysis.

[0025] Preferably, the fault location formula is:

[0026]

[0027] Among them, l a is the distance between the fault point and the substation on the a side of the transmission line; l a,1 is the distance calculated on side a; l a,2 is the distance calculated on the b side of the transmission line; l is the total length of the line;

[0028] is the impedance between the fault point and the substation on side a, is the impedance per unit length of the transmission line; is the measured voltage on side a, is the measured current on side a, K is the zero-sequence compensation coefficient of the transmission line; is the zero-sequence current sensed on side a;

[0029] is the impedance between the fault point and the substation on side b, is the measured voltage on side b, is the measured current on side b, is the zero-sequence current sensed on side b.

[0030] A second aspect of the present invention provides a CT model extension modeling and application system for characterizing device association relationships, using the method according to any one of claims 1 to 9, characterized in that the system comprises:

[0031] Model extension module, used to extend the Private object of the CT model to improve the coil model of the CT model;

[0032] The model association module is used to establish the association relationship between the LN of the protection device and the coil model according to different sampling modes of the protection device;

[0033] The model application module is used to locate the fault according to the CT model including the coil model and its association relationship with the logical node LN of the protection device.

[0034] A third aspect of the present invention provides a terminal, comprising a processor and a storage medium; the storage medium is used to store instructions; the processor is used to operate according to the instructions to execute the steps of the method.

[0035] A fourth aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, which implements the steps of the method when executed by a processor.

[0036] Compared with the prior art, the beneficial effects of the present invention include at least:

[0037] The intelligent substation current transformer CT extended modeling method proposed in the present invention improves and enhances the primary model of the substation, and is conducive to the digitization of the substation structure.

[0038] The extension, association and application method of the substation CT coil model proposed in the present invention can more accurately determine the sampling range of protection, and further can realize the accurate positioning of faults between coils.

[0039] The extended modeling and association method of the substation CT coil proposed in the present invention is helpful to formulate coil configuration rules and realize the inspection of the correctness of the protection sampling configuration. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a flow chart of the method of the present invention;

[0041] Figure 2 Modeling of extended coils for CT models;

[0042] Figure 3 It is a schematic diagram of the sampling circuit of the merging unit;

[0043] Figure 4 It is the relationship diagram of the digital sampling merging unit and the protection virtual circuit;

[0044] Figure 5 This is a circuit diagram for conventional transformers.

[0045] Figure 6 Apply a flow chart for CT modeling;

[0046] Figure 7 The following is a diagram illustrating the application scenario. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The embodiments described in this application are only part of the embodiments of the present invention, not all of them. Based on the spirit of the present invention, other embodiments obtained by ordinary technicians in this field without creative work are all within the scope of protection of the present invention.

[0048] like Figure 1 As shown, Embodiment 1 of the present invention provides a CT model extension modeling and application method for characterizing device association relationships, including:

[0049] Step 1: Expand the Private object of the CT model to improve the coil model of the CT model;

[0050] Further preferably, in order to ensure that there is no dead zone in the coordination between protection devices, it is very important to select the correct CT coil for each protection device. For this purpose, it is necessary to expand the coil information for the CT model of IEC 61850 to ensure the integrity of the model information to better support protection operation and maintenance applications.

[0051] For ConductingEquipment with type = "CTR", extend the Private object to improve the coil model;

[0052] Each coil extends a Private object, whose type attribute value is Winding, and the extension name xmlns is coil="coil.paras.com";

[0053] Then define the coil:no sub-element under the coil Private object to indicate the corresponding coil number, including the attribute name. Under a coil Private object, there is only one coil:no.

[0054] The coil:parameter sub-element is defined under the coil Private object to indicate the parameters of the coil, including the attributes name, desc, dimension and value, which indicate the name, description, dimension and value respectively. Multiple coil:parameters can be defined under one coil Private object.

[0055] The coil:LNode sub-element is defined under the coil Private object, which indicates the logical node of the secondary device associated with the coil. It contains attributes such as lnInst (LN instance), lnClass (logical node type), prefix (prefix), ldInst (LD instance), iedName (IED name), etc., which refer to the corresponding associated logical node; multiple coil:Lnodes can be defined under one coil Private object;

[0056] Under the ConductingEquipment element of type="CTR", a Private object is extended, whose type attribute is "Homonymous Terminal", representing the homonymous terminal, and whose value is the name of the CT terminal (Terminal) close to the homonymous terminal.

[0057] The logical node of the merging unit (acquisition execution unit) should be associated with the coil, and protection equipment and other equipment can indirectly obtain the corresponding CT coil through the virtual loop relationship with the merging unit (acquisition execution unit).

[0058] The schematic diagram of CT model extension coil modeling is as follows Figure 2 shown.

[0059] An example of modeling an extended CT coil is as follows:

[0060]

[0061]

[0062] in<Private type="Homonymous Terminal"> T2 means the end with the same name is close to T2.

[0063] Step 2: According to the different sampling methods of the protection device, the association relationship between the LN of the protection device and the coil model is established.

[0064] Further preferably, in order to describe the corresponding relationship between the protection sampling and the CT, in addition to expanding the CT model to add the definition of the coil, it is also necessary to reflect the association relationship between the LN of the protection device and the coil model to facilitate the analysis of advanced applications.

[0065] According to different sampling modes of the protection device, the present invention proposes two associations of LN.

[0066] (1) Digital sampling: The sampling of the protection device is obtained through the merging unit (MU) or the acquisition execution unit. In this way, the logical node LN "TCTR" (TCTR is the name of the logical node under the process layer access point of the merging unit or the acquisition execution unit) under the process layer access point should be associated with the coil model; the protection device obtains the corresponding sampling virtual signal through the relationship of the process layer virtual circuit, and then indirectly obtains the coil involved in the protection sampling.

[0067] The schematic diagram of the merging unit sampling circuit is as follows: Figure 3 As shown, Figure 4 It is the virtual loop diagram between the merging unit and the protection.

[0068] (2) Conventional analog sampling: The protection device sampling adopts the conventional analog quantity method, directly associating the logical node LN "MMXU" under the protection device station control layer access point (MMXU is the logical node under the protection device station control layer access point) to the coil model proposed in the present invention.

[0069] Conventional transformers use circuits such as Figure 5 shown.

[0070] Step 3: Fault location is performed based on the CT model including the coil model and its association with the logical node LN of the protection device.

[0071] Further preferably, the CT model extension modeling application process and scenario description of the present invention are as follows Figure 6 – Figure 7 As shown in the figure, the required secondary equipment information is obtained through the secondary equipment logical node LN associated with the CT, such as: the high-voltage side coil PTW_H of the main transformer body is connected to the high-voltage side switch bay, and the coil of the bay CT is associated with the main transformer protection telemetry logical node instance signal, which carries the high-voltage side switch current, so as to establish the association between the enumeration signal of the secondary equipment and the actual signal description. Based on the correspondence between the name of the secondary equipment information and the name of the recording channel, the relevant recording channel is automatically matched according to the same name, and the automatic configuration of the recording correspondence is realized. Based on the recording channel, the same source comparison and differential current analysis are carried out. According to the same source comparison and differential current, the fault position can be accurately located.

[0072] Further preferably, the fault location formula is as follows:

[0073] Assume that one end of the line is side a and the other end is side b, I 差流 =Ia-Ib;

[0074] The distance l calculated on side aa,1

[0075]

[0076] in, is the impedance between the fault point and the substation on side a, is the impedance per unit length of the transmission line; is the measured voltage on side a, is the measured current on side a, K is the zero-sequence compensation coefficient of the transmission line; is the zero-sequence current sensed by side a.

[0077] The distance l calculated on the b side a,2 , let the total length of the line be l,

[0078]

[0079] in, is the impedance between the fault point and the substation on side b, is the measured voltage on side b, is the measured current on side b, is the zero-sequence current sensed on side b.

[0080] In summary, the distance l from the fault point to the substation on side a is a for:

[0081]

[0082] Embodiment 2 of the present invention provides a CT model extension modeling and application system for characterizing device association relationships, including:

[0083] Model extension module, used to extend the Private object of the CT model to improve the coil model of the CT model;

[0084] The model association module is used to establish the association relationship between the LN of the protection device and the coil model according to different sampling modes of the protection device;

[0085] The model application module is used to locate the fault according to the CT model including the coil model and its association relationship with the logical node LN of the protection device.

[0086] Embodiment 3 of the present invention provides a terminal, including a processor and a storage medium; the storage medium is used to store instructions; the processor is used to operate according to the instructions to execute the steps of the method.

[0087] Embodiment 4 of the present invention provides a computer-readable storage medium having a computer program stored thereon, which implements the steps of the method when executed by a processor.

[0088] Compared with the prior art, the beneficial effects of the present invention include at least:

[0089] The intelligent substation current transformer CT extended modeling method proposed in the present invention improves and enhances the primary model of the substation, and is conducive to the digitization of the substation structure.

[0090] The extension, association and application method of the substation CT coil model proposed in the present invention can more accurately determine the sampling range of protection, and further can realize the accurate positioning of faults between coils.

[0091] The extended modeling and association method of the substation CT coil proposed in the present invention is helpful to formulate coil configuration rules and realize the inspection of the correctness of the protection sampling configuration.

[0092] The present disclosure may be a system, a method and / or a computer program product. The computer program product may include a computer-readable storage medium carrying computer-readable program instructions for causing a processor to implement various aspects of the present disclosure.

[0093] A computer-readable storage medium may be a tangible device that can hold and store instructions used by an instruction execution device. A computer-readable storage medium may be, for example, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. More specific examples of computer-readable storage media (a non-exhaustive list) include: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disk read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanical encoding device, such as a punch card or a raised structure in a groove on which instructions are stored, and any suitable combination of the foregoing. As used herein, a computer-readable storage medium is not to be interpreted as a transient signal per se, such as a radio wave or other freely propagating electromagnetic wave, an electromagnetic wave propagating through a waveguide or other transmission medium (e.g., a light pulse through a fiber optic cable), or an electrical signal transmitted through a wire.

[0094] The computer-readable program instructions described herein can be downloaded from a computer-readable storage medium to each computing / processing device, or downloaded to an external computer or external storage device via a network, such as the Internet, a local area network, a wide area network, and / or a wireless network. The network can include copper transmission cables, optical fiber transmissions, wireless transmissions, routers, firewalls, switches, gateway computers, and / or edge servers. The network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards the computer-readable program instructions for storage in the computer-readable storage medium in each computing / processing device.

[0095] The computer program instructions for performing the operation of the present disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-related instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages, such as Smalltalk, C++, etc., and conventional procedural programming languages, such as "C" language or similar programming languages. Computer-readable program instructions may be executed completely on a user's computer, partially on a user's computer, as an independent software package, partially on a user's computer, partially on a remote computer, or completely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., using an Internet service provider to connect via the Internet). In some embodiments, an electronic circuit, such as a programmable logic circuit, a field programmable gate array (FPGA), or a programmable logic array (PLA), may be customized by utilizing the state information of the computer-readable program instructions, and the electronic circuit may execute the computer-readable program instructions, thereby realizing various aspects of the present disclosure.

[0096] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents, and any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A CT model extension modeling and application method for characterizing device association relationships, characterized in that: include: The private object Private is extended for the current transformer CT model to improve the coil model of the CT model; According to different sampling modes of the protection device, an association relationship between the logical node LN of the protection device and the coil model is established; Fault location is performed based on the CT model including the coil model and its association with the logical node LN of the protection device.

2. The method for extending and applying a CT model for characterizing device association relationships according to claim 1, characterized in that: The private object Private is extended for the current transformer CT model to improve the coil model of the CT model, including: Under the CT model element of ConductingEquipment of type="CTR", a Private is extended, whose type attribute is "Homonymous Terminal", representing the homonymous terminal, and whose value is the name of the CT endpoint Terminal close to the homonymous terminal; A Private is extended for each coil of the CT model, the type attribute value of which is Winding, and the extended name xmlns is coil = "coil.paras.com"; Define coil:no sub-element, coil:parameter sub-element and coil:LNode sub-element under Private extended by the coil.

3. The method for extending and applying a CT model for characterizing device association relationships according to claim 2 is characterized in that: The coil:no sub-element indicates the corresponding coil number and includes the attribute name; The coil:parameter sub-element represents the parameters of the coil, and includes the attributes name, desc, dimension and value, which represent the name, description, dimension and value respectively; The coil:LNode sub-element represents the logical node of the secondary device associated with the coil, and contains the attributes lnInst, lnClass, prefix, ldInst, and iedName, which respectively represent the LN instance, logical node type, prefix, LD instance, and IED name, which are used to reference the logical node associated with the merging unit, so that the protection device can indirectly obtain the corresponding CT model coil through the virtual circuit relationship with the merging unit.

4. The method for extending and applying a CT model for characterizing device association relationships according to claim 2, characterized in that: Under the coil Private object extended by a coil, there is one and only one coil:no child element, and multiple coil:parameter child elements and coil:LNode child elements are allowed to be defined.

5. The method for extending and applying a CT model for characterizing device association relationships according to claim 1, characterized in that: The sampling method includes a digital sampling method and an analog sampling method.

6. The method for extending and applying a CT model for characterizing device association relationships according to claim 5 is characterized in that: If the protection device adopts digital sampling, the logical node "TCTR" under the process layer access point of the merging unit or the acquisition execution unit is associated with the coil model; the protection device obtains the corresponding sampling virtual signal through the relationship of the process layer virtual loop, and then indirectly obtains the coil involved in the protection sampling.

7. The method for extending and applying a CT model for characterizing device association relationships according to claim 5, characterized in that: If the protection device adopts analog sampling mode, the logical node "MMXU" under the access point of the protection device station control layer is associated with the corresponding coil model.

8. The method for extending and applying a CT model for characterizing device association relationships according to claim 1, characterized in that: The fault location is performed according to the CT model including the coil model and the association relationship between the coil model and the logical node LN of the protection device, including: According to the CT model including the coil model and its association relationship with the logical node LN of the protection device, the required secondary device information is obtained through its associated logical node LN, and the association relationship between the enumeration signal of the secondary device and the actual signal description is established according to the secondary device information; Based on the correspondence between the name of the secondary equipment information and the name of the recording channel, the relevant recording channels are automatically matched according to the same name, and homologous comparison and differential current analysis are carried out based on the recording channels. The fault position is located according to the results of homologous comparison and differential current analysis.

9. A CT model extension modeling and application method for characterizing device association relationships according to claim 1 or 8, characterized in that: The formula for fault location is: Among them, l a is the distance between the fault point and the substation on the a side of the transmission line; l a,1 is the distance calculated on side a; l a,2 is the distance calculated on the b side of the transmission line; l is the total length of the line; is the impedance between the fault point and the substation on side a, is the impedance per unit length of the transmission line; is the measured voltage on side a, is the measured current on side a, K is the zero-sequence compensation coefficient of the transmission line; is the zero-sequence current sensed on side a; is the impedance between the fault point and the substation on side b, is the measured voltage on side b, is the measured current on side b, is the zero-sequence current sensed on side b.

10. A CT model extension modeling and application system for characterizing equipment association relationships, using the method according to any one of claims 1 to 9, characterized in that: The system comprises: Model extension module, used to extend the Private object of the CT model to improve the coil model of the CT model; The model association module is used to establish the association relationship between the LN of the protection device and the coil model according to different sampling modes of the protection device; The model application module is used to locate the fault according to the CT model including the coil model and its association relationship with the logical node LN of the protection device.

11. A terminal comprising a processor and a storage medium; characterized in that: The storage medium is used to store instructions; The processor is configured to operate according to the instructions to execute the steps of the method according to any one of claims 1-9.

12. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the method according to any one of claims 1 to 9 are implemented.

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